Answer:
psychology has to do with the mind and brain while social science has to do with the scientific study if human relationships
The movie Star Wars<span> is a space
opera interstellar epic which uses science and technology in its settings and storylines, although its main
focus is not necessarily on science.</span>
Many
elements in the films appear to defy simple laws of physics.<span>
One of which is the falling of spaceships when they are hit by a laser beam.
Experts said, this is one good example because without gravity in space, ships
should travel in the direction of the impact instead of dropping like a stone.</span>
<span>
</span>
Answer:
Explanation:
We know,
..............(1)
where,
η = Efficiency of the engine
T₁ = Initial Temperature
T₂ = Final Temperature
Q₁ = Heat available initially
Q₂ = Heat after reaching the temperature T₂
Given:
η =0.280
T₁ = 3.50×10² °C = 350°C = 350+273 = 623K
Q₁ = 3.78 × 10³ J
Substituting the values in the equation (1) we get
or
or
⇒ 
Now,
The entropy change (
) is given as:
or
substituting the values in the above equation we get
- The mechanic did 5406 Joules of work pushing the car.
That's the energy he put into the car. When he stops pushing, all the energy he put into the car is now the car's kinetic energy.
- Kinetic energy = (1/2) (mass) (speed²)
And there we have it
- The car's mass is 3,600 kg.
- Its speed is 'v' m/s .
- (1/2) (mass) (v²) = 5,406 Joules
(1/2) (3600 kg) (v²) = 5406 joules
1800 kg (v²) = 5406 joules
v² = (5406 joules) / (1800 kg)
v² = (5406/1800) (joules/kg)
= = = = = This section is just to work out the units of the answer:
- v² = (5406/1800) (Newton-meter/kg)
- v² = (5406/1800) (kg-m²/s² / kg)
= = = = =
v = √(5406/1800) m/s
<em>v = 1.733 m/s</em>
Acceleration = (change in speed) / (time for the change)
Change in speed = (speed at the end) minus (speed at the beginning.
The cart's acceleration is
(0 - 2 m/s) / (0.3 sec)
= ( -2 / 0.3 ) (m/s²) = -(6 and 2/3) m/s² .
Newton's second law of motion says
Force = (mass) x (acceleration) .
For this cart: Force = (1.5 kg) x ( - 6-2/3 m/s²)
= ( - 1.5 x 20/3 ) (kg-m/s²)
= - 10 newtons .
The force is negative because it acts opposite to the direction
in which the cart is moving, it causes a negative acceleration,
and it eventually stops the cart.
